Method for obtaining a soil sample

ABSTRACT

Disclosed is a tool-like cartridge for preserving a soil sample which may be contaminated with a volatile organic compound (VOC). The cartridge includes a barrel and a plug in the barrel for sealing the barrel proximal end during and after sampling and for later expelling the soil sample from such barrel. A threaded portion is on the barrel for attaching a handle and such portion has an opening through it. From the moment of sample extraction until later sample expulsion for analysis, the plug and its resilient seal member substantially prevent vaporized VOC from escaping from the cartridge. A new method for obtaining a soil sample for analysis is also disclosed.

RELATED APPLICATION

This application is a continuation of application Ser. No. 08/241,445filed on May 11, 1994 (and now abandoned) which, in turn, is acontinuation-in-part of application Ser. No. 07/915,309 filed on Jul.20, 1992, and now U.S. Pat. No. 5,343,771.

FIELD OF THE INVENTION

This invention relates generally to devices used for testing and, moreparticularly, to devices used for soil testing.

BACKGROUND OF THE INVENTION

Soil sampling tools and devices are used for a variety of purposes,e.g., to obtain samples for soil moisture content or to sample avolatile organic compound (VOC) which may have permeated the soil. Andsoil cores are removed for other reasons unrelated to VOC analysis.Examples of soil coring and sampling tools are shown in U.S. Pat. Nos.3,326,049 (Eley); 3,444,938 (Ballman); 3,497,018 (Schultz et al.) and4,989,678 (Thompson).

The device shown in the Eley patent has a barrel with air vent and ashaft threaded to the barrel. The shaft is graduated so that whenturned, the soil sample is ejected in increments. The kit shown in theThompson patent includes a sampling device and a sample containmentdevice, both of which are used for analyzing a soil sample containing aVOC.

It is common knowledge that tanks for storing liquids may, over time,develop a leak. If the tank is above ground, the leak is usuallyobserved rather soon after its onset and not much damage results. On theother hand, there is an already-substantial and growing awareness thatcertain types of liquid storage tanks placed underground have agreater-than-normal propensity to deteriorate and leak. Such typesinclude tanks made of common sheet steel from which protective coatingshave either been eaten away or were non-existent. And a substantialfactor contributing to the risk of tank leakage is that with anunderground tank, leakage is not visible. Usually, such leakage can onlybe detected by excavation and testing.

And the risks are enormous. Undetected leaks of underground storagetanks can and do contaminate soil and potable water supplies, the latterby polluting underground aquifers from which a great deal of drinkingwater is drawn. Recent legislation recognizes risks presented by leakingunderground storage tanks and provides for remediation of damage causedby such leaks. Because of the number of gasoline service stations andprivate fuel and solvent storage tanks, leakage of petroleum distillatesand hydrocarbons is a particularly significant problem.

Good remediation requires that personnel be able to accurately determinethe nature and extent of the leak. Such determination depends in largepart upon the availability of high quality test instruments and theability to preserve the integrity of a soil sample (and, particularly,to prevent evaporation of VOCs therein) once the sample is taken. Theefforts of earlier workers in this regard have not been entirelysatisfactory.

For example, the Thompson patent emphasizes speed of transfer of a soilsample from a sampling tool to a containment device to minimize loss ofVOC. This is a less-than-fully-satisfactory solution to retention ofsample integrity, especially if the leaky tank was installed at a sitedistant from the analyst's laboratory. Other known prior art patentsshow soil sampling tools having handles which are not easily removed.And if removable, there is no good way to seal that end of the barrelfrom which the handle is removed. To put it another way, earlier knownsampling tools fail to offer optimum solutions for preserving VOCs insoil samples and for reducing the substantial storage space required totransport what may be dozens of tools to and from a site.

OBJECTS OF THE INVENTION

It is an object of the invention to provide a soil sample containmentcartridge overcoming some of the problems and shortcomings of the priorart.

Another object of the invention is to provide a soil sample containmentcartridge which preserves the integrity of the VOC in a soil sample.

Yet another object of the invention is to provide a soil samplecontainment cartridge which avoids sample contamination.

Another object of the invention is to provide a soil sample containmentcartridge which saves substantial space when transporting samples from apossibly-contaminated site to a laboratory. How these and other objectsare accomplished will become apparent from the following descriptionsand the drawing.

SUMMARY OF THE INVENTION

Aspects of the invention involve a method for obtaining a soil sampleusing a unique tool-like soil sample containment cartridge. Such methodincludes the steps of providing a generally-cylindrical cartridge havingan open distal end and a proximal end sealed by a removable plug. Aremovable handle is attached to the cartridge and the cartridge thenused to "core out" and extract a soil sample.

Following sample extraction, the "mouth portion" at the distal end isclosed, preferably by applying a cap to such mouth portion. For optimumsealing, the applying step includes compressing a resilient seal betweenthe cap and the mouth portion. And the handle is detached but endclosure and handle detachment may be in either order. Using such method,the soil sample and any VOC therewith is quickly "captured" in thecartridge for preservation, transport and later analysis.

In other aspects of the method, the handle detaching step is followed bythe steps of transporting the cartridge for analysis and moving the plugalong the cartridge barrel toward its mouth portion to expel the soilsample from the cartridge. To move the plug, a rod-like implement isprovided for applying force to the plug. The implement is coupled to theplug and the plug and soil sample pushed out.

Structural aspects of the invention involve a tool-like cartridge forpreserving a core-like soil sample after such sample has been removedfrom a site possibly contaminated with VOC. The cartridge has a barrel,a plug in the barrel for expelling a soil sample therefrom and anattachment portion on the barrel and having an opening therethrough. Theplug has a stud extending through the opening and a seal between theplug and the attachment portion prevents VOC from escaping through suchopening. The plug is secured by a nut threaded to the stud. When sosealed, the cartridge is suitable for preserving a soil samplecontaining a volatile organic compound.

More specifically, the plug has an imperforate face plate and a sealingmember is interposed between the face plate and the attachment portionfor sealing the opening. Preferably, such member is a resilient sealsuch as an O-ring.

And if the attachment portion is threaded or otherwise configured foreasy handle attachment and detachment, there is a cover for protectingsuch portion.

At its end opposite the attachment portion, the cartridge has a mouthportion and a cap sealing the mouth portion. Such cap prevents VOCvapors from escaping from the mouth end of the cartridge after sampleextraction and before the sample is transported to and analyzed in alaboratory.

Other aspects of the invention make it easy to expel the well-preservedsoil sample from the cartridge after such cartridge has been transportedto a laboratory. Quick, easy expulsion of the sample to a containmentvial for analysis is important to preserve any VOC present in suchsample.

In a preferred procedure, one (or, more typically, several) cartridgesare supplied to the user, each having its plug stud extended through theopening of its attachment portion and held there by a nut. When the studis so positioned, the sealing member is compressed against theattachment portion and the proximal end of the cartridge is therebysealed. A handle is also supplied.

To collect a possibly-contaminated soil sample, the handle is attachedto the cartridge and the barrel of the assembled tool forced into theearth and then withdrawn with a "core" of soil inside. A cap is promptlyplaced on the mouth portion, the handle is removed and the sample, nowcompletely sealed in the cartridge, is ready to be transported to alaboratory. If the handle is attached to the cartridge by threads, it isdesirable to protect the cartridge threads with a cover after removingthe handle but before cartridge transportation.

The stud includes an interior cavity having a threaded cavity wall. Whenthe lab analyst is ready to expel the sample from the barrel, the nut isremoved and a rod-like implement is attached to the stud for pushing theplug toward the mouth portion and expelling the sample.

Other details of the invention are set forth in the following detaileddescription and in the drawing.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a perspective view of an embodiment of the improved tool withparts broken away and other parts shown in phantom outline.

FIG. 2 is, generally, a cross-sectional view of the tool of FIG. 1 takenalong a viewing plane coincident with the longitudinal tool axis, withparts broken away and other parts shown in full representation.

FIG. 3 is a side elevation view, partly in cross-section, of the toolplunger and ejector.

FIG. 4 is a cross-sectional side elevation view, with parts broken away,showing a variation of a portion of the tool of FIG. 1.

FIG. 5 is a side elevation view, with parts broken away, showing avariation of another portion of the tool of FIG. 1.

FIG. 6 is a representative cross-sectional side elevation view of asuspected leaky underground storage tank site which is to be analyzedusing bored holes.

FIG. 7 is a representative cross-sectional side elevation view of a sitelike that of FIG. 6 which is being analyzed using a dug hole.

FIG. 8 illustrates how a soil sample is ejected into a vial for latersample analysis.

FIG. 9 is a side elevation view of a variation of the tool including abiasing spring.

FIG. 10 is a side elevation view, partly in cross-section and with partsbroken away, of another variation of the tool including a biasingspring.

FIG. 11 is a cross-section elevation view of a new sample-preservingcartridge.

FIG. 12 is a view of a handle used with the cartridge of FIG. 11.

FIG. 13 is a view of a rod-like implement used to urge a soil samplefrom the cartridge of FIG. 11. Part is broken away.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The improved soil sampling tool 10 is particularly useful in collectingsoil samples 11 permeated with a VOC. As described below, the tool 10has new features facilitating sample preservation, storage,transportation and identification. Such features will be welcomed bythose having responsibilities for leak-site analysis and remediation.

Referring first to FIGS. 1 and 2, the improved sampling tool 10 includesa hollow, generally cylindrical barrel 13 having an end wall 15 and amouth portion 17. The interior region 19 of the barrel 13 is ofgenerally uniform diameter along its length and has a volumetriccapacity of 25-30 grams, for example. The edge 21 of the mouth portion17 is bevelled inward, resulting in a relatively sharp soil-cutting"blade."

An elongate, tube-like handle 23 is concentrically attached to thebarrel end wall 15. In a preferred embodiment, the handle 23 isseparably attached to the end wall 15 (by a threaded connection 25, forexample as shown in FIG. 4) so that the handle 23 and barrel 13 can bereadily attached to and detached from one another for purposes describedbelow. The T-shaped handle shown in FIGS. 1 and 2 is preferred insituations where soil samples 11 are expected to be taken from dense,relatively hard soils such as clay soils. The T-shaped handle 23 affordsan opportunity to apply a substantial insertion force to the tool 10.

The handle 23 has a passage 27 extending along its length for receivinga rod-like ejector 29 and the handle 23, passage 27 and ejector 29 arepreferably circular in cross-sectional shape. The diameters of thepassage 27 and the ejector 29 are cooperatively selected to provideslight clearance therebetween so that the ejector 29 may move freelywithin the passage 27.

As best seen in FIG. 2, the barrel 13 has an end aperture 31 and theejector 29 and aperture 31 define an air exhaustion clearance 33 betweenthem. Since there is just enough space between the rim 35 of the plunger37 and the interior wall 39 of the barrel 13 to permit relatively freesliding plunger movement, such clearance 33 permits air to escape alongthe passage 27 as the tool 10 is urged into soil and the plunger 37 isthereby driven toward the end wall 15.

Referring additionally to FIG. 3, a disc-like plunger 37 is mounted tothe distal end 41 of the ejector 29 and has a boss 43 extending a shortdistance from the plunger 37. For reasons described below, the ejector29 and plunger 37 are preferably readily attachable to and detachablefrom one other. In the illustrated exemplary embodiment, the boss 43 hasa threaded pocket 45 and the ejector distal end 41 is similarly threadedfor attachment to the boss 43. At its proximal end 47, the ejector 29includes a thumb engagement member 49 so that when the handle 23 andmember 49 are grasped "hypodermic fashion," the member 49 may bedepressed toward the handle 23 to eject a soil sample 11 from the barrel13. And as shown in FIG. 5, the thumb engagement member 49 may bering-like in shape and a handle 23 with side rings 50 may be providedinstead of the T-shaped handle 23 shown in FIGS. 1 and 2.

Since such samples 11 are usually transported to a laboratory foranalysis, it is highly preferred that VOC vapors be prevented fromescaping from the sample 11 and from the tool 10 through the aperture31. Diminution of the amount of vapor and VOC present in the sample 11will "skew" the test results and may cause the level of soilcontamination to appear less than it actually is. Accordingly, theplunger boss 43 seals the aperture 31 when the plunger 37 is closelyadjacent to or in contact with the barrel end wall 15. Sealing is by aresilient O-ring 51 seated in a circumferential groove in the outersurface of the boss 43.

It is highly preferred that the aperture 31 be sealed even as the toolbarrel 13 starts penetrating into the soil. In the embodiments describedabove, the plunger 37 may be spaced away from the barrel end wall 15when penetration starts, especially if the tool 10 is prior held withthe barrel 13 downward. Referring to FIGS. 1 and 9, the plunger 37 isbiased by a spring 89a or 89b to the sample-extracting position, i.e.,that position at which the plunger 37 seals the aperture 31. In thatway, VOC vapors are prevented from escaping through the aperture,especially at the onset of sample "cutting."

In the arrangement of FIG. 1, the compression spring 89a is interposedbetween the handle 23 and the thumb engagement member 49. In thearrangement of FIG. 9, the tension spring 89b is attached to and extendsfrom the side rings 50 downward (as viewed in FIG. 9) along the handle23. A coupler rod 91 extends between the lower end of the spring 89b anda collar 93 immediately below the member 49. In each instance, thespring 89a, 89b biases the ejector 29 and its plunger 37 upward to sealthe aperture 31. The aperture 31 may be sealed by an O-ring 51 on theplunger boss 43 as described below.

In the arrangement of FIG. 10, the tool 10 includes a hollow tube 95received telescope-fashion in the handle 23. The upper end 97 of thetube 95 is attached to a thumb engagement member 49 as is the ejector29. A compression spring 99 is confined between the lower end 101 of thetube 95 and the top of the barrel 13. The spring 99 biases the tube 95,member 49 and ejector 29 upward in the absence of downward force on themember 49.

Referring further to FIGS. 1 and 2 and to FIG. 8, it is preferred thatthe barrel interior region 19 be completely sealed after a soil sample11 is taken but before the sample 11 is ejected to a vial 53 for sampleanalysis. To that end, the improved tool 10 also includes a cup-like cap55 which has an interior cavity 57 and a cavity wall 59. The cap cavity57 has a cross-sectional shape generally conforming to that of thebarrel 13 which, in the preferred embodiment, is cylindrical. Aresilient O-ring 51a is seated in a circumferential groove 61 formed inthe cavity wall 59. Such O-ring 51a helps assure a vapor-tight sealagainst the mouth portion 17 when the cap 55 is placed on such portion17.

It should be understood that sealing the barrel interior region 19 canbe accomplished in other ways. For example, the boss 43 and aperture 31can be formed to permit very closely fitted, sliding clearance betweenthem and thereby provide a relatively good vapor seal. The barrel outerwall 63 and the cap cavity wall 59 can be similarly formed. However, useof O-ring seals 51, 51a permits some "forgiveness" in certainmanufacturing dimensional tolerances and should result in a reducedmanufacturing cost.

As explained in the summary, when O-rings 51, 51a are used for sealing,some difficulty may be experienced in positioning the sealing "pieces"(the boss 43 or the cap 55) to a fully seated position if the pieces arenot made to close tolerances. If needed, a seal lubricant 65 may beapplied to the rings 51, 51a and nearby surfaces to help avoid suchdifficulty. However, care must be taken to avoid sample contamination bya petroleum-based product such as a lubricating oil. Therefore, a highlypreferred lubricant 65 is powdered graphite.

The following is an explanation of how and where soil samples 11 aretaken and identified and how such samples 11 are handled in preparationfor lab analysis. It is assumed that the site 67 of a suspected leakingunderground storage tank has been identified and such site 67 is showngenerally in FIGS. 6 and 7. As shown in FIG. 6, those involved indetermining whether and to what extent contamination exists at the site67 will bore holes 69 (to avoid sampling at the earth surface where VOCand vapors may be less concentrated) and use what is known as a splitspoon device 71 (resembling a "plunge type" post hole digger) to extractrelatively large "slugs" 73 of soil from various holes 69. Using thetool 10, a soil sample is taken from a location 75 (or perhaps two ormore locations) on the slug 73. Each slug 73 is removed at a known depthand from a hole 69 have a known location. Both such informational itemsare recorded for "mapping" the site 67 with a field sketch.

Referring to FIG. 7, in another approach, a hole 77 is dug in the earth.Samples are taken at various horizontally and vertically spacedlocations 75 along the generally vertical wall 79 of the hole 77 and,probably, at other locations. The wall 79 and the locations 75 willsimilarly be mapped with a field sketch.

Irrespective of whether bored or dug holes 69, 77 are used, each suchsample location 75 is identified on the sketch with a designator 81which is unique for that site 67. It is likely that soil samples 11 willbe taken from several dozen locations 75 at a particular site 67. Forreasons that will become apparent, sampling a site 67 therefore involveshaving a substantial number of tools 10 available, i.e., at least aquantity equal to the number of locations 75.

Referring again to FIG. 1, the designator 81 used for a particularlocation 75 is that which is marked on the tool 10 used to take thatparticular sample 11. The designator 81 is preferably prominently markedon the tool 10, e.g., on the barrel. Since a particular tool 10 will beused many times (at different sites 67) and since such tools 10 must bethoroughly washed and cleaned prior to use, marking is preferablypermanent by etching, engraving or the like.

Immediately after the sample 11 is taken (and before significant VOCevaporation can occur), the barrel 13 with the possibly-contaminatedsoil sample 11 inside is then sealed as described above and the tool 10set aside. The overall length of the tool 10 may be two or three timesthe length of the barrel 13 alone. Clearly, provision of adequatestorage and carrying space for several dozen complete tools 10 becomes asignificant concern, especially at a remote field site 67 where workingconditions may be less than ideal. In a preferred sampling tool 10, thehandle 23 and ejector 29 may be removable from the barrel 13 and plunger37, respectively. When removed, the aperture 83 is plugged for vaporretention using a plug 85 like that shown in FIG. 4. And, of course,"sample loaded" tools 10 can be stored as is without removing the handle23 and ejector 29.

Referring to FIG. 8, when all desired samples 11 have been taken, the"sample-loaded" tools 10 are used to place soil samples 11 into vials 53kept on site 67. Such samples 11 are later analyzed at a laboratory. Andeach sample 11 is placed into a vial 53 marked with the same designator81 as is marked on the tool 10 and on the field sketch. The tool 10thereby becomes the link between a particular location 75 and aparticular vial 53 and helps establish a sample "chain of custody".

Sample placement is by uncapping the barrel 13, quickly inserting suchbarrel 13 into a vial 53 and manipulating the ejector 29 to drive thesample 11 into the vial 53 for virtually-immediate vial capping. In ahighly preferred version, the tool barrel 13 has an outside diameter notin excess of, and preferably very slightly less than, about 25 mm. Sincemany types of appropriately-sized lab vials 53 have a mouth diameter of25 mm or greater, such a barrel 13 can be readily inserted into suchvials and, of course, into vials 53 having larger mouths. As illustratedin FIG. 8, an appropriately-sized barrel 13 closely fits the diameter ofthe vial mouth 87 to help prevent vapors from escaping.

Referring also to FIGS. 11 and 12, another aspect of the inventioninvolves a tool-like cartridge 113 for preserving a core-like soilsample 11 after such sample 11 has been removed from a site 67 possiblycontaminated with VOC. A major advantage of the cartridge 113 is that itcan be used "on-site" to quickly and completely seal apossibly-contaminated soil sample 11 within such cartridge 113immediately upon withdrawal of the tool barrel 13a from the soil.Another advantage of such cartridge 113 is that it can be carried "sanghandle" for space-saving transportation of the confined soil sample 11to a laboratory.

The invention has a number of new features configured and arranged topreserve the integrity of a soil sample 11 after it has been extractedand up to actual analysis. The new cartridge 113 has a generallycylindrical barrel 13a with a mouth portion 17a bounded by a relativelythin knife-like edge 21a so that the cartridge 113 may be more easilyurged into the earth. At its proximal end 115 opposite the mouth portion17a, the barrel 13a has an attachment portion 117 to which the threadedend 119 of a handle 23a is attached during actual sample extraction.

The barrel attachment portion 117 and the distal end 119 of the handle23a are compatibly threaded. The handle 23a can thereby be easilyattached to the barrel 13a for sampling and thereafter just as easilydetached from such barrel 13a for transporting the sample.

The structural arrangement that seals the proximal end 115 of thecartridge 113 is as follows. The attachment portion 117 has a"smooth-bore" opening 121 through it and within the barrel 13a is a plug123 having an imperforate, disc-like face plate 125 and a stud 127 ofreduced diameter extending from such plate 125. The end 129 of stud 127is externally threaded and also has a threaded interior cavity 131. Theplug 123 seals an end 115 of the barrel 13a during sample extraction andtransport and, as described in more detail below, is later used to expelthe soil sample from the cartridge 113.

A sealing member 133 such as a resilient O-ring is interposed betweenthe face plate 125 and the attachment portion 117. After the stud 127 isinserted through the opening 121, a retention device 135 such as a nutis threaded to the stud 127. When the nut is tightened, the O-ring iscompressed and the opening 121 is sealed. And there is a cover 137 onthe attachment portion 117 as a thread protector when a handle 23a isnot attached.

Referring also to FIG. 2, a cap 55 seals the mouth portion 17a. Asdescribed above, the cap 55 has an O-ring 51a in a groove 61 and whenthe cap 55 is in place, the O-ring 51a is compressed and seals againstthe mouth portion 17a. Like the plug 123, such cap 55 prevents VOCvapors from escaping from the cartridge 113 after sample extraction,while the sample 11 is being transported to a laboratory and until theanalyst is ready to remove the cap 55 and expel the sample 11 into avial for analysis.

Other aspects of the invention involve a method for obtaining a soilsample using the unique tool-like cartridge 113 described above. Suchmethod includes the steps of providing a generally-cylindrical cartridge113 having an open mouth portion 17a and a proximal end 115 sealed by aremovable plug 123.

In preferred practice (and prior to shipment to the customer), thecartridge manufacturer or distributor installs the removable plug 123 byinserting the stud 127 through the opening and tightening the nut. Ifthe prospective user, e.g., an environmental engineering company, hasnot earlier obtained a suitable handle 23a, such handle 23a is orderedto be supplied with the cartridge 113 or with a group of cartridges 113.

As the user prepares to take a soil sample, the end 119 of the removablehandle 23a is attached to the cartridge 113. The cartridge 113 then usedto "core out" and extract a soil sample 11.

Immediately following sample extraction, the mouth portion 17a isclosed, preferably by applying a cap 55 to such mouth portion 17a. Foroptimum sealing, the applying step includes compressing the resilientseal 51a between the cap 55 and the mouth portion 17a. And the handle23a is detached but end closure and handle detachment may be in eitherorder but is preferably done in the order described. Using such method,the soil sample 11 and any VOC therewith is quickly "captured" in thecartridge 113 for preservation, transport and later analysis.

In other aspects of the method, the handle detaching step is followed bythe steps of transporting the cartridge 113 for analysis and, when readyto analyze the sample, moving the plug 123 along the cartridge barrel13a toward its mouth portion 17a to expel the soil sample from thecartridge 113. To move the plug 123, a rod-like implement 139 (as shownin FIG. 13) is provided for applying force to the plug 123. Theimplement 139 is coupled to the plug 123 by screwing the implement end141 into the threaded interior cavity 131 of the plug 123. The plug 123and soil sample 11 are then pushed out.

It has been found that the new cartridge 113 and the method of its useare major advances in soil VOC analysis since the soil sample need notbe removed from the cartridge 113 to be transported. And the integrityof the sample 11 (and any VOC vapors contained therein) is wellmaintained by the sealing means 51a, 133 at each end of the cartridge113. That is, VOC vapors are substantially prevented from escaping andcontaminants are prevented from entering.

And those are not the only advantages. In practice, users of thecartridge 113 are often repeat purchasers thereof and have obtained ahandle 23a with their first cartridge purchase. Similarly, the analyzinglaboratory has obtained a rod 139 to urge the plug 123 toward thecartridge mouth portion 17a. Thereafter, it is necessary to supply onlycartridges 113 to the user, to ship only soil-containing cartridges 113to a laboratory and to ship the dirty cartridges 113 back to a cleaningsite for cleaning and later re-use. That is, no handle 23a or implement139 need accompany the cartridge. The aggregate saving in shipping spaceis very significant.

While the principles of this invention have been described in connectionwith specific embodiments, it is to be understood clearly that suchembodiments are exemplary and not limiting.

What is claimed:
 1. A method for obtaining a sample of soil which may contain a volatile organic compound, the method including the steps of:providing a cartridge having a single wall, an open mouth portion having a cutting edge and a proximal end sealed by a plug; urging the cartridge into the surface of soil to extract a soil sample from a location adjacent to such surface while retaining the proximal end sealed; closing the mouth portion while retaining the proximal end sealed; transporting the cartridge to a laboratory while retaining the mouth portion closed and the proximal end sealed; and moving the plug to expel the sample from the cartridge directly into a laboratory vial.
 2. The method of claim 1 wherein the plug moving step is preceded by the steps of:providing an implement for applying force to the plug; and coupling the implement to the plug. 